title: Classroom sex composition and first-grade school outcomes: The role of classroom behavior.
abstract: Using nationally representative data from the Early Childhood Longitudinal Study-Kindergarten Cohort (N=21,409; 10,452 girls and 10,957 boys; mean age=7.24years), the association between first-grade classroom sex composition (CSC), measured as the percentage of female students, and end of the year academic (reading, mathematics) and socio-emotional (externalizing problems, internalizing problems, self-control, interpersonal skills) outcomes was examined. Using multilevel modeling techniques and controlling for prior achievement levels, CSC was positively associated with children's reading achievement at the end of first grade; students performed better in reading in classes with a higher percentage of female students. CSC was also associated with three of the socio-emotional outcomes; controlling for prior levels, students in classrooms with a higher percentage of girls had better self-control and interpersonal skills and fewer internalizing problems. Classroom behavior mediated the effects of CSC on reading achievement and the socio-emotional outcomes. Implications for the composition of first-grade classrooms are discussed.
authors.affiliation: Whitman College, United States. Electronic address: pahlke@whitman.edu.
authors.forename: Erin
authors.initials: E
authors.lastname: Pahlke
authors.forename: Carey E
authors.initials: CE
authors.lastname: Cooper
authors.forename: Richard A
authors.initials: RA
authors.lastname: Fabes
keywords: Achievement; Classroom behavior; ECLS-K; First grade; Sex composition; Socio-emotional outcomes